Forming-free resistive switching with low current operation in graphene-insulator-graphene structures

Graphene as a conducting electrode has attracted significant attention due to its low sheet resistance, high flexibility and high transparency [1]. Recently, high out-of-plane resistance of graphene has been utilized to reduce the operating current in metal oxide based resistive memories (RRAMs) [2]. However, this report also indicates that the high out-of-plane resistance of graphene contributes to the requirement of high-voltage forming (6 V) [2]. Since the forming step requires significantly higher voltage compared to regular set/reset operations, elimination of the forming step while maintaining the low-current operability is important for graphene RRAMs.In this work we demonstrate forming-free resistive switching in graphene-insulator-graphene (G-I-G) structures with graphene used as both top and bottom electrodes.